YSK: if a parent or grandparent was born in Ireland or Northern Ireland, you are automatically eligible for Irish Citizenship regardless of current nationality
Why YSK: it's a simple and cheap process which grants you the right to visit, live and work in Ireland and the entire European Union. You don't even need to renounce your current citizenship, you can get a dual passport*
*as commenters have pointed out, some countries don't allow their citizens to hold a dual passport